The present disclosure relates to a technical field of charging operations, and more particularly to a charging method of controlling output voltages, an apparatus, and an adapter.
Currently, electronic devices, such as mobile phones, are installed with rechargeable batteries and thus, adapters can charge the batteries.
In charging operations, the adapters convert alternating current voltage into direct current voltage by a power converter and transmit the direct current voltage to the electronic devices. This can cause an adapter to output a larger voltage, which results in damage and even can cause the batteries to explode which seriously affects safety of the batteries.
In a related art output voltage control method, a controller and a digital potentiometer are installed in the adapter. The controller controls the digital potentiometer by inter-integrated circuit (I2C) instructions in the adapter, so that electrical levels of feedback pins of an alternating current-direct current (AC-DC) control chip in the power converter change. The AC-DC control chip then adjusts the output voltage of the power converter based on electrical level changes of the feedback pins and thus, increasing safety of the batteries.
However, costs of the digital potentiometer are high and at least two feedback pins are used to transmit the I2C instructions to control the digital potentiometer. In other words, in order to control the digital potentiometer, occupation of the at least two feedback pins of the controller affects use efficiency of the controller.